Vol.52 No.12 December 2004

Usefulness of levofloxacin at 200 mg b.i.d. for suspected pneumococcal pneumonia

Yoshihito Niki¹⁾, Toshiharu Matsushima²⁾, Keizo Yamaguchi³⁾, Shigeru Kohno⁴⁾, Akira Watanabe⁵⁾, Shigeki Odagiri⁶⁾, Nobuki Aoki⁷⁾ and Atsushi Saito⁸⁾

¹⁾Division of Respiratory Disease, Department of Medicine, Kawasaki Medical School, 577 Matsushima, Kurashiki, Okayama, Japan
²⁾Respiratory Center of Junpukai Kurashiki Daiichi Hospital
³⁾Department of Microbiology, Toho University
⁴⁾Second Department of Internal Medicine, Nagasaki University, School of Medicine
⁵⁾Respiratory Oncology and Molecular Medicine, Institute of Development, Aging, and Cancer, Tohoku University
⁶⁾Odagiri Respiratory Disease Clinic
⁷⁾Department of Internal Medicine, Shinrakuen Hospital
⁸⁾Department of Internal Medicine I, Faculty Medicine, University of the Ryukyus

Abstract

We studied the efficacy and safety of levofloxacin (LVFX) at 200 mg b.i.d. for 7 days, and the correlation between efficacy and the AUC/MIC ratio in patients with suspected pneumococcal pneumonia. Subjects were suspected of having mild to moderate pneumococcal pneumonia because pneumococcal antigen was detected in the urine or Gram staining of sputum was positive before the start of treatment. We measured blood LVFX twice in each patient and used the Bayesian method with population parameters to calculate AUC.
Of the 71 subjects enrolled, 57 were analyzed for clinical efficacy, and efficacy was 93.0% (53/57). Of these, 46 had pneumococcal pneumonia, diagnosed as positive for Streptococcus pneumoniae by culture or urinary antigen. Efficacy was 93.5% (43/46). Of the 30 in whom S. pneumoniae was isolated and identified, bacterial eradication was 96.7% (29/30).
Side effects occurred in 17 of 70 patients, i.e., 15 mild, and LVFX administration was continued. Two had moderate side effects and recovered quickly after LVFX administration was discontinued.
The AUC/MIC ratio calculated for 22 patients in whom the MIC of LVFX for S. pneumoniae could be measured was 68.5± 31.9 (mean± S.D.). Of these, only 1 patient was AUC/MIC< 25.
Considering from above results, it was suggested that 200 mg LVFX administered twice a day could achieve an adequate AUC/MIC ratio and high clinical efficacy in patients with suspected pneumococcal pneumonia.

Key word

levofloxacin, Streptococcus pneumoniae, PK/PD, AUC/MIC, pneumonia

Received

August 23, 2004

Accepted

October 28, 2004

Jpn. J. Chemother. 52 (12): 793-803, 2004